PHIL 804 Selected Topics in Philosophy of Science: Philosophy of Biology

Rationality of Evolution and Evolution of Rationality

Fall Semester 2012 | Evening | Vancouver


INSTRUCTOR Christopher Stephens 


We will focus on two kinds of questions about evolution and rationality.

(1)  What are the similarities and differences between rational deliberation and evolution by natural selection? At first glance, these appear quite different: deliberation is a mental process whereas evolution by natural selection applies to any heritable trait. Rational deliberation depends on subjectively based goals whereas natural selection depends on the objective property of fitness. Both processes, however, are optimizing ones – rational deliberation favours the act with the highest expected utility; natural selection favours the trait with the highest fitness. Some have suggested that a good heuristic for determining what natural selection favours is to ask whether a rational agent would prefer the trait in question. To what extent are these parallels substantive and to what extent are they superficial? What happens when problems in rational decision theory are moved to an evolutionary framework and vice versa? One of the main goals of the course will be to develop a deeper understanding of both standard models of rationality and of evolutionary theory.

(2)  What reasons (if any) are there for thinking that natural selection will favour rationality? This is an interesting question in light of two considerations: first, psychological evidence suggests that we’re often rather irrational, and second, many – indeed most – organisms get along just fine (from an evolutionary point of view) without the ability to engage in rational deliberation. Some scholars have suggested that natural selection will favour rational or reliable beliefs; others have been skeptical of any such connection. We will examine this debate in detail, including a look at some models of the evolution of the emotions, moral psychology, and religious belief, since some argue that these are sources of irrationality. Along the way, we will consider some general issues in the philosophy of biology about the power of natural selection and how evolutionary hypotheses are tested.


  • Presentation (20%) Each student is expected to give an in-class presentation (with an associated presentation paper of about 4-5 double-spaced pages) once during the term. I will pass around a sign up sheet on the first day.
  • Weekly Participation (20%) You are expected to write a short (1-2 pages, double-spaced) paper each week (except for the week of your presentations) on some issue in that week’s readings as well as participate actively in class discussion (including asking questions about the other students’ presentations). Weekly papers will be marked on a “pass-fail” basis.
  • Term Paper (60%) You must write an approximately 5,000-word term paper on some issue concerning evolution and rationality. The final paper is due December 19th but a version of your term paper must also be presented in class on Nov. 28th. You must get your topic approved by November 14th.

 Background in one or more of the following will be especially useful: decision & game theory, evolutionary biology, psychological studies of human reasoning, philosophy of biology and philosophy of mind. There are no official prerequisites, and I will not assume a detailed knowledge of any of these areas, although I will assume that you have some general philosophical sophistication. For each topic, I have included both required readings and optional background readings. Those with less prior exposure to these areas are advised to do more of the optional readings. Please be sure to read Sober’s “Three Differences...” article for the first meeting. Download the course reading schedule